Segments or segment-of-one
Estimate the net value per send of six segments and of one email per person for a win-back program, with checking costed, and pick one.
On this page
Two proposals for the same monthly email: six segments, or one generated email per person. The estimate turns on a cost the second proposal leaves out.
The situation
A self-serve product sends a monthly win-back email to 30,000 lapsed users. At the course's email rates, 40% open, 5% of opens click and 10% of clicks reactivate, and each reactivation is worth $800 of expected margin. A marketing hour costs $100.
Proposal A: six segments by plan and last feature used, each a generated and reviewed variant at under $1 plus a $50 review, with 4 hours to define the segments. Assume a 10% relative lift over one message.
Proposal B: one email per person, 30,000 variants at about $0.01 each, built from the same segment data plus each user's history, with the same 4 hours of setup. Assume a further 3% relative lift on top of the segments. Nobody can read 30,000 emails, so the brand lead wants a random sample reviewed at a minute each, enough to show fewer than 1 in 1,000 are wrong: with none found wrong, 3 ÷ 0.001 = 3,000 emails. At two-sided α = 0.05 and 80% power, confirming a 3% relative lift on a 2% click rate takes about 867,000 recipients an arm.
The question
Estimate the net value per send of each proposal against one message, and decide which one ships.
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